A streamlined protocol for the use of the semi-sitting position in neurosurgery: A report on 48 consecutive procedures

Abstract

The semi-sitting position has lost favor among neurosurgeons partly due to unproven assumptions of increased complications. Many complications have been associated with this position; the most feared: venous air embolism and paradoxical air embolism. We report on this retrospective study of the outcome over 4 years of 48 neurosurgical patients operated on consecutively using a standardized protocol: 41 (85%) in the semi-sitting position, and seven (15%) in the prone position. Procedures included: tumor resection (34), posterior fossa decompression (12), cyst resection (1) and resection of arteriovenous malformation (1). Pre-operative workup was standardized. Vigilant intra-operative observation was done by an experienced neuroanesthetist. Pertinent data was extracted from surgical records. Of the 48 patients, 10 (20.8%) were found to have a patent foramen ovale (PFO) on trans-esophageal echocardiography. Of these, four (40%) patients underwent procedures in the semi-sitting position while six (60%) did not. A clinically significant venous air embolism (VAE) was detected during 2 of the 41 semi-sitting procedures (4.9%). Neither patient suffered any obvious sequelae. No other morbidity was encountered associated with surgical position. Our study suggests that a model similar to ours is effective in preventing major complications associated with the semi-sitting position. The semi-sitting position is a safe, practical position that should be considered in appropriate cases. The fear of dreadful complications seems unwarranted.

Simultaneously Combined Anterior‐Posterior Approaches for Subaxial Cervical Circumferential Reconstruction in a Sitting Position

“…In a sitting position operation, in addition to the special management of patients' tracheal intubation, the literature that reported serious complications may occur such as an air embolism 26 . But a recent retrospective study of the outcome of neurosurgical patients operated in a semi-sitting position showed that clinically significant venous air embolism was rare (4.9%) and nonfatal 27 . Moreover, in our study there was no additional morbidity.…”

Sitting position awake craniostomy with drainage for chronic subdural hematoma: A viable alternative?

“…Nevertheless, in neurosurgery, the sitting position is usually linked with complications (venous air embolism in particular), although recent studies demonstrated decreased rates of complications in patients undergoing surgeries in the sitting position. [13,14] Nevertheless, anesthesiologists and surgeons continue to avoid this position. [15] Up to date, no reports of patients undergoing craniostomy in the sitting position for CSDH have been published.…”

Venous air embolism in neurosurgery

“…3 The risk of developing a VAE exists for all kinds of neurosurgical procedures; however, its incidence is higher for procedures requiring the patient to be in a sitting 4 or semisitting position. 5,6 The incidence of air embolism in the sitting position is variable but has been described in up to 45% of the cases. 7 It may also occur with the patient in lateral decubitus, supine or prone position.…”